1. Field of the Invention
The present disclosure relates to an image-processing apparatus, an image-processing method, and a computer program product.
2. Description of the Related Art
Techniques for performing image processing of dot images have been conventionally disclosed.
The following technique is disclosed by JP-A-2003-168119: a technique of repeating collation with respect to a binary image while repeating correction using dilation processing of a dot character by using, as a structuring element, four pixels adjacent to a pixel of interest from the top, bottom, left and right, until the shape of the dot density obtained by projecting the dot character coincides with an aimed pattern.
The following technique for separating a halftone dot area and a character area in a binary image is disclosed by JP-A-2012-156839: a technique of finding a candidate of halftone dot area by dilation processing and erosion processing by using, as a structuring element, eight pixels adjacent to and centered on a pixel of interest, and when the area size is small, deciding that the character is false-detected and detecting only the halftone dot area.
However, the conventional image-processing apparatus (see JP-A-2003-168119, for example), which performs a morphological operation on only a binary image and performs recognition processing and separation processing, has a problem of not capable of performing correction processing on a multivalent image.